Pressure transmitting device



PRESSURE TRANSMITTING DE'VICE Filed April 3o. 1957 y BY A424741,

United States Patent-' D bce 2,941,367 rl'urssURE TRANsrnrrnvG DEVICE chant- $101111 schwaarbx River Grove', u1. Brock Equipment Company, 4525 N. Ravenswoo'd Ave., Chicago 40, Ill.)

FrieaApr. so, 1957-, ser. No. 656,067 7 (ci. sof-:54.61

This invention relates to a pressure transmittingv device aud-more particularly to such a device for transmitting pressure from a vsource of operating fluid to a uid operated element without a uid connection therebetween.

An object of this invention is to provide a new and improved device for transmitting pressure from a source of operating uid to a uid operated element without any fluid connection therebetween.

Another object of the invention is to provide a pressure transmitting device for transmitting pressure from a Asource of operating uid to a uid operated element in which there is no uid connection between said source and said element and which may be of substantial length and has a major part of its length formed of electrically nonconducting material to permit use of the device on and in the area of energized electrical conductors.

. A further object of the invention is to provide a device for transmitting uid pressure from a source of operating fluid to a fluid operated element having a rst means movable in response to the pressure of the operating uid exerted thereon, a second means movable to exert pressure on another body of fluid communicating with the iiuid operated element, and means connecting said iirst and second means for movement together to transmit force from said iirst means to said second means.

Anadditional object of the invention is to provide a hydraulic hot stick for transmitting pressure from a source of uid to a fluid operated tool or the like comprising, means adapted for connection to the sourceV of uid including a cylinder having a piston Amovable therein,- means adapted to receive a tool VorV the like and have fluid cornmunication therewith including a cylinder and a piston movable therein, electrically nonconducting means for connecting said cylinders in 'ixed relation to each other including an elongated hollow tube connected between the cylinders, electrically nonconducting means for connecting said pistons together for simultaneousV movement including anrelongated rod extending through and slidably connedkin saidrtube and connected between said pistons, andiluid seal means for sealing the cylinders from the hollow tube.

The objects of the invention generally set forth t'ogether with other ancillary advantages are attained by the construction and arrangementrshown by way of illustration in theaccompanying drawing, in which:

y Eig. 1 is a view in elevation of the pressure transmitting device, with a compression tool or the like mounted at one end thereof, and a source of operating fluid connected to the other end thereof;

Y Fig. 2 is a plan section of the pressure transmitting devicetaken generally along the line 2--2 in Fig. 1, with 85 the tool and source of operating uid detached from the device; p

Fig. 3 is a vertical section taken generally alongV the line in Fig. `2; and K i 'Fig. 4 is a plan section taken along the 1ine4 -'4 in The pressure transmitting device is indicated generally y2,941,367 Patented Jurre 21, 1960 2, at A. As shown' in Fig. 1, for the purposes of villustration the device A mayV haveV a hydraulic compressionftool- 1 attached at one end`- thereof; and aA source' 2f of s operating iluid connected to theother end thereof. The source -2 may'connect with a pump o'r to aline providing?, a source of operating uid under pressure.

The pressure 'transmitting device,l A lhasy` meansladapted for connection to the source 2 of operating fluid-'comprising a metaly cylinder 3 ofaluminum or the like in which a piston 4 is slidably mounted and having .an-inlet passage 5 for the operating lluid. Any O-ringy 6 surrounds the piston so as to form a seal with an inner wall ofthe cylinder 3.

The pressure transmitting device A- has means adapted to receive av tool or the like and haveuid communication therewith comprising a second-metalcylinder-10of aluminum or the like inY which a piston 1v1 is movably mounted and having an outlet passage 12 fromv an end of the cylinder. An 0-ring-.13 surroundsv the piston 11 to provide a seal with van inner Wall of the' cylinder'ltl.

Means for connectingy said cylinders together' in fixed relation to each other comprises an elongated, hollow connection in the form of a tube 15 secured atl its opposite ends to metal ferrules 16 and '17, respectively, by suitable connections such as the threaded conections 18 and-.19. The ferrules 16 and 17 threadably-connect with; open ends of the cylinders 3- and 10, theA ferrule 16 having. a threaded connection 20 with the cylinder 10, andthe ferrule 17 having a threaded connection 21 with the cylinder 3.

Means are provided for connecting the pistons 4v and 11 together for simultaneous movement- .including4 an elongated connecting member in the form of a r od 25 extending through and slidably coniined in the hollow tube 15.. The rod 25 passes through apair of bores 26 and 27 in the ferrulesA 16 `and 17, respectively, and into the cylinders 3 and 10. Thebores 26 and 27 each' h as an O-ring 28A and 29, surrounding thev rod 25, respectively, for sealingthe cylinders 3 and 10 from iluid communication with the hollow tube 1,5. Y l A When oil is pumped under pressurel into the hrsg-cylinder 3, the piston, 4 will advance towardthe left, as viewed-in Fig. 2, which, through the connecting rod-.257, will advance the piston V11 toward the left; andlthelevfthand end of cylinder 10 having been previously filled with uid, the duid will be forced out ofthe second cylinder 10 to the hydraulically operated member such as a piston inthe tool 1. As shown inthe drawing,l thecylinders 3 andl andthe pistons 4 and 11 are ofthe vsame size so that the outlet pressure from the second cylinderwllvlwill be the same as the inlet pressure into therst cylinder '3. The piston 4 defines a fluid chamber in the cylinder 3 extending tothe inlet passage 5.y The pistonll defines a iiuid chamber in the cylinder 10 extending to the outlet passage 12,. Y A 1 Although a tool 1 is shown in association with the pressure transmitting device A, it is readily apparent that this devicemay be used toY operate any member responsive to hydraulic pressure. The device may be iformed from parts made `of metal or other material capable of withstanding the forces exerted, particularly the tension forces in the hollow tube 15, and the compression forces in the connecting rod 25. vv l I The device A is readily usable as a hydraulic hot stick, in which case the hollow tube l15 and connecting rod 25 would be formed of electrically nonconducting material. The tube 15 has a relatively'thick wall and may be suitably fo'rmed of woven glass ber larn'inat'ions'bondedwith a plastic resin such as a phenolic formaldehyde, polyester, or epoxy resin. Y The connecting rod 25 v may besuitably formed from a plastic resin as, for example, 'an epoxy,

rovings for reinforcement. In operating compression tools, oil pressures of up to 10,000 p.s.i. may be encountered, and it would be necessary to have metal reinforcements in any hose` designed to withstand thisV pressure with the result that such ahose would be a conductor'. This problem is overcome in the disclosed device, and avoids any tiuid connection through the major part of the length of the device. The pressure transmitting device transmits hydraulic pressure from a sourceof power to the operating device without any metallic or iiuid contact therebetween. Y

A spring 30 surrounds one end ofthe connecting rod 25 and engages between the ferrule 17 and the piston 4 to function as a return spring for the pistons 4 and 11. The connecting rod25 is secured at each of its ends to the adjacent piston by a ball and socket joint to permit the -piston'to freely slide in its cylinder in` the event slight bending should occur in the rod 25. This ball and socket joint is formed, as shown in Fig. 4, by providing a slightly concave surface 31 in the piston and rounding an end 32 of the connecting rod 25. A split collar 33 is tted in an annular groove 34 in an end of the connecting rod 25, and a threaded ring 35 Ifor retaining the split collar is threaded into the piston, as shown at 36.

In order to retain fluid in the cylinders 3 and 10, one part of a two-part high-pressure quick coupler may be associated with the inlet passage and the outlet passage 12. A suitable coupler is that offered by Pioneer Hydraulics Co., Inc., as its Item No. 3000 in which a complete coupler has a male half and a female half with a ball mounted in each half, so that, when the source 2 or -device such as tool 1 is attached, the ball in the cornponent of the coupler carried thereby will engage and move the ball in the component secured to the pressure transmitting device A to place the parts in fluid communication.

I claim: v

l. A hydraulic hot stick for transmitting hydraulic pressure from a source of operating fiuid to a fluid operated-)tool or the like, comprising, in combination, means adapted for connection to the source of operating fluid including a metal cylinder having an inlet passage at an end thereof for `operating uid and a cylindrical piston movably mounted in the cylinder forming a fluid chamber in the cylinder between the pis-ton and the inlet passage, means adapted to receive a tool and have fluid communication therewith for exerting iiuid pressure on the tool including arnetal cylinder having a uid outlet passage at an end thereof and a cylindrical piston movably mounted in the cylinder forming a fluid chamber in the cylinder between the piston and the outlet passage, said cylinders land said pistons being of substantially the same diameter, electrically nonconducting means for connecting said cylinders in fixed spaced end-to-end relation to each other including an elongated hollow tube of glass fiber 'reinforced plastic resin, a metal ferrule threadably connecting each end ofthe tube one to each of the other ends of said cylinders, electrically nonconducting means for connecting said pistons together for simultaneous movement including an elongated rod of glass fiber reinforced plastic resin'slidably confined in said tube and havtion, means adapted for connection to the source of operating fluid including a cylinder having an inlet adjacent an end thereof for operating fluid and a piston movably mounted in the cylinder, means adapted to have fluid communication with said device for exerting fluid pressure on the device including a cylinder having a fluid outlet adjacent au end thereof and a piston movably mounted in the cylinder, electrically nonconducting meansfor connectingsaid cylinders in fixed spaced end-to-end relation to each other including an elongated hollow tube having a length many times greater than its diameter and having.

its ends secured one toeach of the cylinders, electrically nonconducting means for connecting said pistons together for simultaneous movementincluding a rod extending slidably through s'aid tube and having its ends extending within the cylinders and secured one to each ofthe pistons, and fluid sealing means for sealing the cylinders from the hollow tube.

Y `4. A hydraulic hot stick as defined in claim 3, wherein each end vof the rod andthe associated piston vare shaped to provide a ball and socket connection to permit slight pivoting of the rod relative to the piston and prevent relative longitudinal movement therebetween, and a return spring mounted in one of the cylinders and engageable with the piston therein :for urging the piston in adi- -rection opposing the force of the operating fluid.

5. A portable device for transmitting pressure from a source of operating fluid to a iiuid operated tool element comprising, a first cylinder havinga piston therein movable in response to the pressure of the operating uid exerted thereon, a second cylinder having a piston therein for exerting pressure on another body of fiuid for operating the tool element, a hollow 'tube formed of elec- .ing its ends extending through Vthe other ends of the cylinders and secured one to each of the pistons by a ball and socket type joint, and fluid sealing rings in said ferrules in engagement with the rod for sealing the cylinders from the hollow tube. Y

2. A hydraulic hot stick as defined in claim l, and having a return spring mounted in the cylinder adapted for connection to the source of operating fluid, said spring being in engagement with the piston therein for urging the piston toward said inlet passage.

3. A portable hydraulic hot stick for transmitting pres- `sure from a source .of operating uid to a fiuid operated .device carried on thehot stick comprising, in combinatrically nonconducting material connecting the cylinders together in fixed spaced end-to-end relation to each other, and an elongated rod formed of electrically nonconducting material slidably confined throughout the length of said tube and connecting said pistons together for simultaneous movement to transmit pressure from the operating fluid to said other body of iiuid.

6. A portable hot stick device for transmitting pressure from a source of operating fluid to a fluid operated element carried on the devicecomprising, a first cylinder having a piston thereinmovable in response to the pressure of the operating fluid exerted thereon, a second cylinder having a piston therein for `exerting pressure on another body of fluid, an elongated electrically nonconducting member connecting said pistons together for simultaneous movement to transmit force from 'the operating fluid to said other body of uid, and elongated electrically nonconducting means connecting the cylinders together in fixed relation to each other and slidably conlining said elongated member.

7. A portable hydraulic hot stick for transmitting the force of hydraulic pressure a substantial distance, in lieu of, a hose, from a source of operating fluid under pressure toa iiuid operable tool, comprising, in combination, means adaptedrfor connection to a source of operating fluid including a cylinder having aninlet passage adjacent one end thereof for operating fluid and a piston slidable into the cylinder forming a fluid chamber in the cylinder between the piston and the inlet passage, means adapted to carry a tool and have iiuid communication therewith for exerting uid pressure on the tool including a cylinder having av fluid outlet passage at one end thereof and a piston slidable in the cylinder forming-a fluid chamber in the cylinder between the piston and the outlet passage, means connecting the cylinders in fixed spaced end-to-end relationship to each other including a long slender electrically nonconducting tube and means xedly connecting opposite ends of the tube to the other cylinder ends respectively, said tube having a Alength'substantially'greater than the length ofzthe cylinders and many times greater than the diameter ofthe tube, means connecting the pistons together for simultaneous movement including an elongate electrically nonconductive rod having a portion of substantial length slidably conned throughout the length of said tube for reinforcement and means connecting opposite ends of the rod respec- 5 tively to the pistons, and fluid sealing rings around the rod for preventing leakage of fluid from the cylinders to the tube.

References Cited in the le of this patent 10 UNITED STATES PATENTS 661,839 Adams Nov. 13, 1900 836,630 Caskey Nov. 20, 1906 1,507,390 Loughead Sept. 2, 1924 15 1,898,376 McCulloch et al. Feb. 21, 1933 6 Schmidt et al. Apr. 17, Carroll June 15, Chase Oct. 29, Greenberg July 18, Johnson June 17, Kane Aug. 9, Randol Nov. 20, Szappanyos Dec. 9,

FOREIGN PATENTS France Mar. 3, France June 13. France Jan. 20, France Feb. 23, Great Britain Nov. 23, Great Britain June 20, 

